1. Field of the Invention
This invention relates to a radiation-shielding injector for a radiopharmaceutical liquid composition. More particularly, it relates to a radiation-shielding injector accompanied with a syringe-type vial filled with a radiopharmaceutical liquid composition, which is so designed as to prevent the fingers or the body of an operator from radiation exposure on administration.
2. Prior Art
Conventionally, the radiopharmaceutical liquid composition is contained in a glass vial and tightly sealed with a rubber septum. On practical applications at diagnostic or therapeutic institutions, such as hospitals, the radiopharmaceutical liquid composition is once transferred to a disposable syringe and administered to the patient, so that the radiation exposure of the operator becomes a serious problem. Recently, with a high demand for preventing the operator from radiation exposure on transference, there has been proposed a syringe-type container filled with a radiopharmaceutical liquid composition, which is usable as a kit in association with additional assemblies such as a needle and a plunger, whereby no transference of the radiopharmaceutical liquid composition becomes necessary.
The commercially available syringe-type containers comprise in general three assemblies, i.e. an outer lead cylinder, a middle plastic cylinder and an inner syringe-type glass vial or container inserted thereinto. Due to such a construction, the entire size of the container inevitably becomes so large that the administration is cumbersome and inconvenient. Further, the conventional containers have the disadvantage that a firm attachment of the middle plastic cylinder as well as the inner syringe-type glass vial or container to the outer lead cylinder can not be stably performed and a large part of the assembly is contaminated with radioactive material, thereby causing a serious social problem in disposal of a large number of radioactive wastes.